Preferred trace weighting velocity spectrum calculating method

The invention provides a preferred trace weighting velocity spectrum calculating method, which comprises the following steps: selecting seismic trace data, the cophasal axis time difference of which is larger, of a reflecting interface in CMP trace gather; calculating an offset weighting coefficient according to geophone offset information; and calculating preferred trace weighting velocity spectrum according to the weighting coefficient. The preferred trace weighting velocity spectrum calculating method takes the trace time difference of cophasal axes of the same reflecting interface in the trace gather into consideration when calculating the velocity spectrum, selects seismic traces, the cophasal axis time difference of which is larger, and carries out weighting through the geophone offset information, so that obvious suppression of velocity spectrum noise generated by coherent noise is realized, velocity spectrum resolution is high, velocity analysis accuracy is improved, and manual or automatic velocity p